Polycythaemia rubra vera presenting with depression: recognising the syndrome abulia.

A patient with polycythaemia rubra vera is described, presenting primarily with symptoms attributed to depression. While in the ward she developed a stroke, confirmed on CT scan of the head. Venesection alone produced marked improvement in her neurological and psychiatric symptoms. The clinical picture corresponds most accurately to the neurological syndrome of abulia, which is an important differential diagnosis of depression with psychomotor retardation. The pathophysiology of impaired cerebral blood flow causing neuropsychiatric symptoms in polycythaemia is discussed.